4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Samuel Neves <[email protected]>

commit e78e5a91456fcecaa2efbb3706572fe043766f4d upstream.

In the __getcpu function, lsl is using the wrong target and destination
registers. Luckily, the compiler tends to choose %eax for both variables,
so it has been working so far.

Fixes: a582c540ac1b ("x86/vdso: Use RDPID in preference to LSL when available")
Signed-off-by: Samuel Neves <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Andy Lutomirski <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/x86/include/asm/vgtod.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/include/asm/vgtod.h
+++ b/arch/x86/include/asm/vgtod.h
@@ -93,7 +93,7 @@ static inline unsigned int __getcpu(void
         *
         * If RDPID is available, use it.
         */
-       alternative_io ("lsl %[p],%[seg]",
+       alternative_io ("lsl %[seg],%[p]",
                        ".byte 0xf3,0x0f,0xc7,0xf8", /* RDPID %eax/rax */
                        X86_FEATURE_RDPID,
                        [p] "=a" (p), [seg] "r" (__PER_CPU_SEG));


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